Biological growth plate scanner with automated intake

ABSTRACT

The invention is directed to a biological scanner for scanning biological growth plates. The biological growth plate is loaded into the biological scanner via motorized rollers, and an actuator presses the growth plate against a platen once the growth plate is drawn to a scanning position within the scanner. The biological scanner then generates one or more images of the growth plate. Moreover, sensors can be arranged to facilitate sensing and positioning of the growth plate in a plurality of locations for imaging different parts of the plate. Additional embodiments are directed to features such as a hinged door that facilitates access to the scanner, and footings disposed on various sides of the scanner to facilitate flip-over of the scanner for simplified use by right-handed or left-handed users.

FIELD

The invention relates to biological scanners for analysis of biologicalgrowth plates and detection of bacteria or other biological agents infood samples, laboratory samples, and the like.

BACKGROUND

Biological safety is a paramount concern in modern society. Testing forbiological contamination in foods or other materials has become animportant and often mandatory requirement for developers anddistributors of food products. Biological testing is also used toidentify bacteria or other agents in laboratory samples such as bloodsamples taken from medical patients, laboratory samples developed forexperimental purposes, and other types of biological samples. Varioustechniques and devices can be utilized to improve biological testing andto streamline and standardize the biological testing process.

A wide variety of biological growth plates have been developed. As oneexample, biological growth plates have been developed by 3M Company(hereafter “3M”) of St. Paul, Minn. Biological growth plates are sold by3M under the trade name PETRIFILM plates. Biological growth plates canbe utilized to facilitate the rapid growth and detection of bacteria orother biological agents commonly associated with food contamination,including, for example, aerobic bacteria, E. coli, coliform,enterobacteriaceae, yeast, mold, Staphylococcus aureus, Listeria,Campylobacter, and the like. The use of PETRIFILM plates, or othergrowth media, can simplify bacterial testing of food samples.

Biological growth plates can be used to enumerate or identify thepresence of bacteria so that corrective measures can be performed (inthe case of food testing) or proper diagnosis can be made (in the caseof medical use). In other applications, biological growth plates may beused to rapidly grow bacteria or other biological agents in laboratorysamples, e.g., for experimental purposes.

Biological scanners refer to devices used to scan or count bacterialcolonies, or the amount of a particular biological agent on a biologicalgrowth plate, or the like. For example, a food sample or laboratorysample can be placed on a biological growth plate, and then the platecan be inserted into an incubation chamber. After incubation, thebiological growth plate can be placed into the biological scanner forautomated detection and enumeration of bacterial growth. Biologicalscanners automate the detection and enumeration of bacteria or otherbiological agents on a biological growth plate, and thereby improve thebiological testing process by reducing human error.

SUMMARY

In general, the invention is directed to a biological scanner forbiological growth plates. A biological growth plate is inserted into thebiological scanner. Upon insertion of the biological growth plate, thebiological scanner generates an image of the plate. Then, the amount ofbiological agents that appear in the image, such as a number of bacteriacolonies, can be counted or otherwise determined using image processingand analysis routines performed either by the biological scanner or anexternal computing device, such as a desktop computer, workstation orthe like. In either case, the biological scanner automates the analysisof biological growth plates.

The biological scanner incorporates an automated loading mechanism tofacilitate handling and analysis of biological growth plates by thescanner. The automated loading mechanism is configured to draw thegrowth plate into the scanner and place the growth plate in a scanningposition. In particular, the biological growth plate is loaded into thebiological scanner via motorized rollers or another transport mechanism,and an actuator presses the growth plate against a platen once thegrowth plate is drawn to a scanning position within the scanner. Thebiological scanner then generates one or more images of the growthplate.

Sensors can be arranged to facilitate sensing and positioning of thegrowth plate in a plurality of positions to scan different parts of thegrowth plate. For example, a first scanning position may correspond toan indicia on the growth plate and a second scanning position maycorrespond to a location of biological agents on the biological growthmedium. Also, a hinged door may facilitate access to the scanner, andfootings disposed on various sides of the scanner may facilitateselective positioning of the scanner in an inverted orientation forsimplified use by right-handed or left-handed users.

In one embodiment, the invention provides a biological scanner forscanning a biological growth medium. The scanner comprises a transportmechanism to draw the biological growth medium into the biologicalscanner, a platen within the biological scanner, and one or more sensorsto detect when the biological growth medium is drawn to a scanningposition adjacent the platen. The scanner also includes an actuator topress the biological growth medium against the platen when the one ormore sensors detect that the biological growth medium is drawn to thescanning position, and an imaging device to generate an image of thebiological growth medium when the biological growth medium is pressedagainst the platen.

In another embodiment, the invention provides a biological scanner forscanning a biological growth medium. The scanner comprises a housing andan imaging device to generate an image of the biological growth mediumwhen the biological growth medium is within the housing. The scanneralso includes a first set of footings on a first side of the housing,and a second set of footings on a second side of the housing such thatthe biological scanner can be positioned on either of the first orsecond set of footings.

In another embodiment, the invention provides a biological scanner forscanning a biological growth medium. The scanner comprises a housingformed with a hinged door, and an imaging device to generate an image ofthe biological growth medium when the biological growth medium is withinthe housing. The scanner also includes a set of rollers to draw thebiological growth medium into the biological scanner, the set of rollersincluding a first subset of rollers disposed on the hinged door and asecond subset of rollers that abut the first subset of the rollers whenthe hinged door is closed.

In another embodiment, the invention provides a biological scanningsystem comprising a biological scanner for scanning a biological growthmedium. The scanner comprises a transport mechanism to draw thebiological growth medium into the biological scanner, a platen withinthe biological scanner, one or more sensors to detect when thebiological growth medium is drawn to a scanning position adjacent theplaten, an actuator to press the biological growth medium against theplaten when the one or more sensors detect that the biological growthmedium is drawn to the scanning position, and an imaging device togenerate an image of the biological growth medium when the biologicalgrowth medium is pressed against the platen. The system also includes acomputer coupled to the biological scanner and including a processorthat counts biological agents in the medium based on the image.

In another embodiment, the invention provides a method comprisingreceiving a biological growth medium in a biological scanner, drawingthe biological growth medium to a first scanning position within thescanner and generating a first image of the biological growth medium.The method also includes drawing the biological growth medium to asecond scanning position within the scanner, and generating a secondimage of the biological growth medium.

Various aspects of the invention may provide a number of advantages. Forexample, the invention may ensure that a biological growth plate can beinserted into a biological scanner, properly positioned within thescanner, imaged or otherwise scanned to identify or enumerate amounts ofbiological agents, and then ejected from the biological scanner in anautomated fashion. In particular, the sensor configurations describedherein can automate the insertion and positioning of biological growthplates in a manner that ensures that reliable imaging can occur, therebyimproving the integrity of automated scanning of such biological growthplates. Automation of the ejection of the plate from the biologicalscanner can also simplify the process for a user.

In addition a hinged door can allow for simplified access to theinterior of the scanner. Accordingly, the scanner components can becleaned or repaired with greater ease. Also, a hinged door allows forsimplified alleviation of jams or other problems within biologicalscanner. In addition, footings disposed on various sides of the scannerprovide flexibility in terms of the input and output locations of thescanner. A user, for example, may position the scanner on a given set offootings based on the users preferences or the work environment in whichthe scanner is used.

Additional details of these and other embodiments are set forth in theaccompanying drawings and the description below. Other features, objectsand advantages will become apparent from the description and drawings,and from the claims.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of a biological scanner according to oneembodiment of the invention.

FIG. 2 is a perspective view of an exemplary system comprising abiological scanner coupled to an external computer which performsimaging analysis of the images generated by the biological scanner.

FIG. 3 is a cross-sectional top view of a biological scanner accordingto an embodiment of the invention.

FIG. 4 is another cross-sectional top view of the biological scannerillustrated in FIG. 3.

FIG. 5 is a cross-sectional front view of the biological scannerillustrated in FIGS. 3 and 4.

FIGS. 6A and 6B are perspective views collectively illustrating abiological scanner that includes sets of footings disposed on differentsides of the scanner.

FIG. 7 is a flow diagram illustrating operation of an exemplarybiological scanner in accordance with an embodiment of the invention.

DETAILED DESCRIPTION

The invention is directed to a biological scanner for biological growthplates, or other biological growth media. In accordance with theinvention, the biological growth plate is loaded into the biologicalscanner via motorized rollers or another transport mechanism, and anactuator presses the growth plate against a platen once the growth plateis drawn to a scanning position within the scanner. The biologicalscanner then generates one or more images of the growth plate. Animaging device such as a 2-dimensional monochromatic camera can bepositioned within the scanner to generate one or more images of thegrowth plate when the growth plate is pressed against the platen.

Sensors can be arranged to facilitate sensing and positioning of thegrowth plate in a plurality of locations for imaging different parts ofthe growth plate. For example, the growth plate may be sensed and imagedat a first location to generate an image of indicia, such as a bar code,on the growth plate. The indicia may identify the plate or type ofplate, so that appropriate scanning and image processing routines can beselected. For example, different processing routines may be performed tocount biological growth on the growth plate based on the indicia. In anycase, the growth plate can be moved to a second location to generate oneor more images of the biological agents on the growth plate. Anarrangement of sensors automate the positioning and movement of thegrowth plate through the scanner. Alternatively, the imaging devicecould be used to detect positioning of the growth plate, instead ofsensors.

Also described is a hinged door of a biological scanner that facilitatesaccess to the interior of the scanner. A subset of the rollers can bedisposed on the hinged door, such that the rollers on the door contactother rollers when the door is closed. A motor drives at least some ofthe rollers to draw the growth plate through the scanner.

In addition, footings may be disposed on various sides of the scanner tofacilitate flip-over of the scanner for simplified use by right-handedor left-handed users In particular, footings can be disposed on varioussides of the scanner to facilitate flexibility in terms of the input andoutput locations of the scanner. A user may position the scanner on agiven set of footings based on the users preferences or the workenvironment in which the scanner is used.

Various aspects of the invention may be useful with a variety ofbiological growth plates. For example, the invention may be useful withdifferent plate-like devices for growing biological agents to enabledetection and/or enumeration of the agents, such as thin-film cultureplate devices, Petri dish culture plate devices, and the like.Therefore, the term “biological growth plate” will be used broadlyherein to refer to a medium suitable for growth of biological agents topermit detection and enumeration of the agents by a scanner. Many typesof growth plates or media could also be used in accordance with theinvention.

FIG. 1 is a perspective view of a biological scanner 10 in accordancewith one embodiment of the invention. As illustrated, biological scanner10 is designed to receive a biological growth plate 12. In particular,biological scanner 10 includes a housing 16 that defines an input slot18 for receiving biological growth plate 12. A guide mechanism 13 may beformed on housing 16 to aid insertion of biological growth plate 12 intobiological scanner 10. Biological scanner 10 also includes an ejectionslot (not shown), through which growth plate 12 is ejected followingimaging of growth plate 12.

Biological scanner 10 may also include other features, such as a displayscreen (not shown) to display the progress or results of analysis of thebiological growth plate to a user. In some embodiments, biologicalscanner 10 includes an internal processor for analyzing the images ofgrowth plate 12. In other embodiments, however, the processing of imagesoccurs external to biological scanner 10, e.g., in a desktop computer,workstation, or the like. In the latter case, biological scanner 10 mayinclude an interface to allow biological scanner 10 to becommunicatively coupled to another computer.

Biological scanner 10 houses an imaging device, such as a 2-dimensionalmonochromatic camera for generating one or more images of an insertedbiological growth plate 12. In addition, biological scanner 10 may housevarious illuminators for illuminating the front and back of biologicalgrowth plate 12 during imaging. The illuminators can illuminatebiological growth plate 12 with one or more colors, and one or moreimages of growth plate 12 can be generated and then analyzed todetermine bacteria counts on growth plate 12.

Growth plate 12 may include a growth area 17 where bacteria or otheragents manifest on growth plate 12. Growth area 17 may be a flat surfaceor a recessed well. A determination of whether a given sample beingtested in growth plate 12 is acceptable, in terms of bacterial colonycounts, may depend on the number of bacterial colonies per unit area.Accordingly, images generated by biological scanner 10 can be used toquantify the amount of bacterial colonies per unit area on plate 12. Thesurface of biological growth plate 12 in growth area 17 may contain oneor more growth enhancing agents designed to facilitate the rapid growthof one or more types of bacteria or other biological agents. In somecases, biological growth plate 12 is incubated prior to insertion intobiological scanner 10.

Growth plate 12 may also include indicia 19, such as a bar code or othertype of identification marking used to identify growth plate 12. Forexample, indicia 19 may identify the type of bacteria or biologicalagent being grown and tested on growth plate 12. Biological scanner 10can be designed to draw growth plate 12 into scanner to a first locationand generate an image of indicia 19, and then draw growth plate 12 to asecond location and generate an image of growth area 17. In this manner,images of indicia 19 and growth area 17 can be generated by biologicalscanner 10. Alternatively, a single image may capture both indicia 19and the growth area 17. In either case, scanning indicia 19 canfacilitate identification of the type of plate being used and scanninggrowth area 17 and thereby improve automated counting of biologicalagents grown on plate 12.

By way of example, growth plate 12 may comprise a biological growthplate sold by 3M under the trade name PETRIFILM plates. Growth plate 12can be utilized to facilitate the rapid growth and detection of bacteriaor other biological agents commonly associated with food contamination,including, for example, aerobic bacteria, E. coli, coliform,enterobacteriaceae, yeast, mold, Staphylococcus aureus, Listeria,Campylobacter, or the like.

FIG. 2 is a perspective view of an exemplary system 21 comprising abiological scanner 20 coupled to an external computer 22 which performsimaging analysis of the images generated by the biological scanner.External computer 22 may include, for example, a microprocessorprogrammed for image analysis of biological growth plate 24. Externalcomputer 22 may comprise a personal computer (PC), desktop computer,laptop computer, handheld computer, workstation, or the like. Forexample, software programs can be loaded on external computer 22 tofacilitate image analysis of images of biological growth plate 24generated by biological scanner 20.

Biological scanner 20 is coupled to external computer 22 via interface25. Interface 25, for example, may comprise a Universal Serial Bus (USB)interface, a Universal Serial Bus 2 (USB2) interface, an IEEE 1394FireWire interface, a Small Computer System Interface (SCSI) interface,an Advance Technology Attachment (ATA) interface, a serial ATAinterface, a Peripheral Component Interconnect (PCI) interface, aconventional serial or parallel interface, or the like.

FIG. 3 is a cross-sectional top view of a biological scanner 30, whichmay correspond to biological scanner 10 or biological scanner 20. Asshown in FIG. 3, biological scanner 30 comprises a housing 31 thathouses an imaging device 32, such as a camera and one or moreilluminators 33A, 33B for illuminating a growth plate to be imagined.Circuitry 34 controls imaging device 32 and illuminators 33 in order togenerate one or more images of a growth plate.

By way of example, imaging device 32 may comprise a 2-dimensionalmonochromatic camera and illuminators 33 may comprise three-colorilluminators that selectively illuminate the growth plate with one ormore colors. Various monochromatic images of the growth plate can begenerated by imaging device 32 when the growth plate is illuminated bythe one or more colors.

Housing 31 defines a guiding mechanism 35 to aid insertion of growthplates into biological scanner 30. A user, for example, may insert agrowth plate between guiding mechanism 35 and actuator 47, whichtypically includes a pressure plate and may also include various backilluminators. Actuator 47 is solenoid driven to press and release thegrowth plate against a platen 41. When pressed against platen 41, thegrowth plate is positioned in the focal plane of imaging device 32.Various motorized rollers can grasp the growth plate and draw the growthplate into biological scanner 30 for imaging.

In particular, biological scanner 30 includes a set of rollers 36A, 36B,37A, 37B which draw the growth plate into biological scanner 30 andautomate movement of the growth plate through scanner 30. Other types oftransport mechanisms could also be used, however, instead of rollers. Inthe exemplary embodiment illustrated in FIG. 3, a first subset ofrollers 36A, 36B may comprise segmented rubber rollers driven by motor38 via belt 39. Motor 38 may comprise a direct current (DC) motorresponsive to sensors that detect positioning of the growth plate. Inthis manner, rollers 36A, 36B are motor-driven to facilitate automatedmovement of a growth plate through scanner 30.

A second subset of rollers 37A, 37B may comprise spring loaded pressurerollers that abut rollers 36A, 36B and provide a bias force such that agrowth plate can be drawn between the set of rollers 36A, 36B, 37A, 37Bby movement of subset of rollers 36A, 36B. Spring loaded rollers 36A,36B, for example, may provide an amount of spring bias that accommodatesdifferent growth plates of different widths. Also the set of rollers36A, 36B, 37A, 37B may be positioned sufficiently close to one anotherto ensure that the smallest desired growth plate can be drawn throughscanner 30. Again, rollers 36A, 36B, 37A, 37B generally comprise onetype of transport mechanism that may be used in accordance with theinvention. However, other types of transport mechanisms couldalternatively be used.

Biological scanner 30 comprises a platen 41 and an actuator 47 thatpresses a biological growth plate against platen 41 when the biologicalgrowth plate is positioned in a desirable scanning position. Inparticular, actuator 47 can press the growth plate against platen 41 toensure the growth plate is in the focal plane of imaging device 32.Rollers 36A, 36B, 37A, 37B can draw the growth plate to the desiredscanning position and actuator 47 can press the growth plate againstplaten 41. Illuminators 33A, 33B illuminate the growth plate with one ormore colors and one or more images are generated by imaging device 32. Aset of sensors (not shown in FIG. 3) can automate the detection andpositioning of the growth plate at the desired scanning position.Alternatively, imaging device 32 could be used to detect positioning ofthe growth plate, instead of sensors.

Actuator 47 may comprise another platen such that when actuator 47presses the growth plate against platen 41, the growth plate issandwiched between two platens. Additional back illuminators 42 canprovide back illumination to the growth plate during imaging. In somecases, back illuminators 42 are disposed on a platen that forms part ofthe actuator. In that case, actuator 47 further includes a three colorillumination system, which may incorporate red, green and blue (RGB)illumination LEDs. The RGB LEDs may provide side illumination toactuator 47 and thereby provide back illumination to a biological growthplate that rests between actuator 47 and platen 41. In addition, similarRGB illumination LEDs may be used to provide top illumination. In otherwords, illuminators 33A, 33B may also comprise RGB illumination LEDs.

Actuator 47 may be solenoid driven. In that case, actuator, 47 comprisesone or more solenoids 44A, 44B that cause movement of actuator 47. Forexample, solenoids 44A, 44B may be disposed on opposing sides of backilluminators 42 to press both sides of a growth plate against platen 41.Once the biological growth plate is positioned at a desired location oneor both of solenoids 44A, 44B cause actuator 47 to press the growthplate against platen 41. Illumination and imaging is then be performed.Again, a sensor arrangement facilitates detection of the growth plate atone or more desirable locations within biological scanner 30. In oneexample, actuator 47 is spring biased against platen, and solenoids 44A,44B engage to overcome the spring bias. In other words, one or both ofsolenoids 44A, 44B may disengage to cause actuator 47 to press againstplaten 41, and engage to cause actuator 47 to release from platen 41.

Upon illumination, imaging device 32 captures one or more images of thebiological growth plate and provides the image(s) to a processor foranalysis. The processor may be housed within biological scanner 30 ormay be an external processor within another computer such as a desktopcomputer or workstation. In one example, imaging device 32 comprises amonochromatic imaging device that captures monochromatic images of thebiological growth plate. For example, the biological growth plate may beilluminated by one or more red LEDs, at which time imaging device 32generates a first image. Then, the biological growth plate may beilluminated by one or more green LEDs, at which time imaging device 32generates a second image. Finally, the biological growth plate may beilluminated by one or more blue LEDs, at which time imaging device 32generates a third image.

The processor (either internal to scanner 30 or external) receives themonochromatic images and performs analysis on the images in order togenerate a bacterial colony count. The use of a monochromatic imagingdevice 32 to generate one or more separate monochromatic images mayimprove image resolution for each color, and at the same time, canreduce implementation costs associated with imaging device 32. Thedifferent images may also be combined by the processor for viewing oranalysis purposes.

In some embodiments, scanner 30 may process images of differentbiological growth plates according to different image processingprofiles. The image processing profiles may be selected based on userinput or identification of the type of biological growth plate presentedto scanner 30. The image processing profile may specify particular imagecapture conditions, such as illumination intensities, exposuredurations, and colors, for capturing images of particular plate types.Thus, the scanner may apply different image capture conditions,including different illumination conditions, in processing images ofdifferent biological growth plates. Moreover, identification of anindicia on the growth plate may allow for selection of image processingprofiles in an automated fashion.

As an illustration, some types of biological growth plates may requireillumination with a particular color, intensity and duration. Inaddition, some biological growth plates may require only front or backillumination, but not both. For example, an aerobic count plate mayrequire only front illumination as well as illumination by only a singlecolor such as red. Alternatively, an E. coli/Coliform plate may requireonly back illumination and a combination of red and blue illumination.Similarly, particular intensity levels and durations may be appropriate.For these reasons, illumination may be controlled in response to imagecapture conditions specified by an image processing profile, which maybe identified by the indicia 19 on growth plate 12.

After the growth plate has been scanned, rollers 36A, 36B, 37A, 37B caneject the growth plate from ejection slot 48. Another growth plate maythen be inserted into biological scanner 30.

FIG. 4 is another cross-sectional top view of biological scanner 30. Asshown in FIG. 4, housing 31 may define a hinged door 49 that can befixed in a closed position via locking mechanism 45. Hinged door 49facilitates easy access to the interior of biological scanner 30.Accordingly, cleaning and maintenance of various components ofbiological scanner 30 can be performed by opening door 49 as shown inFIG. 4. Also, hinged door 49 can be useful for providing access toalleviate jams or other problems within biological scanner 30.

Rollers 36A, 36B, motor 38, belt 39, and solenoids 44A, 44B are housedwithin door 49. When hinged door 49 is closed and locked into place vialocking mechanism 45 (as shown in FIG. 3), rollers 36A, 36B disposed ondoor 49 abut rollers 37A, 37B. When hinged door 49 is open (as shown inFIG. 4) rollers 37A, 37B are not biased against rollers 36A, 36B.

FIG. 5 is a cross-sectional front view of biological scanner 30illustrating a sensor arrangement that facilitates automated intake ofbiological growth plates. In particular, biological scanner includes aset of sensors 52A, 52B, 52C that detect positioning of a biologicalgrowth plate and automate movement of rollers 36A, 36A′, 36B, 36B′ andactuator 47 (FIG. 3) in order to facilitate positioning of the growthplate for imaging. Rollers 36A and 36A′ may be driven along shaft 53 androllers 36B and 36B′ may be driven along shaft 54. Sensors 52 may bedisposed on door 49 or adjacent platen 41. Sensors 52 may compriseoptical sensors, or any other type of sensor capable of sensing a growthplate.

When a growth plate is inserted into biological scanner 30 along guidingmechanism 35, first sensor 52A detects the presence of the growth plateand causes motor 38 to drive rollers 36A, 36A′, 36B, 36B′ via belt 39 inorder to draw the growth plate into biological scanner 30. When secondsensor 52B detects the growth plate, movement of motor 38 is temporalityterminated and solenoids 44A, 44B cause actuator 47 to press the growthplate against platen 41 (see FIG. 3). In particular, second sensor 52Bcorresponds to a first desirable scanning position of growth plate,e.g., a location where indicia 19 (FIG. 1) of growth plate 12 can beimaged.

Once one or more images of indicia 19 are generated, solenoids 44A, 44Bcause actuator 47 to release the growth plate from platen 41. Again, theimages of indicia 19 can be used to identify growth plate 12 andfacilitate selection of a counting algorithm useful for the identifiedplate. Motor 38 drives rollers 36A, 36A′, 36B, 36B′ via belt 39 in orderto draw the growth plate further into biological scanner 30. When thirdsensor 52C detects the growth plate, movement of motor 38 is againterminated and solenoids 44A, 44B cause actuator 47 to press the growthplate against platen 41 (see FIG. 3). In particular, third sensor 52Ccorresponds to a second desirable scanning position of growth plate 12,e.g., a location where growth area 17 (FIG. 1) of growth plate 12 can beimaged.

In other words, sensors 52A-52C control the processing flow throughbiological scanner 30. First sensor 52A detects the growth plate andinitiates the process of drawing growth plate 12 into biological sensor.Second sensor 52B detects growth plate 12 at a first scanning positionand causes imaging to occur. After imaging, growth plate 12 is drawnfurther into biological scanner 10. Third sensor 52C then detects growthplate 12 at a second scanning position and causes imaging to occuragain. Growth plate 12 is then ejected from biological scanner 30.Numerous other sensor arrangements could also be defined. In general,the set of sensors 52 facilitate automated intake and processing ofbiological growth plates by detecting the location of a growth plate andcausing actions to occur at proper times so that desired images of thegrowth plate can be generated, including an image of indicia carried bythe growth plate and an image of the growth area of the growth plate. Inother embodiments, however, imaging device 32 (FIG. 3) may be used tofacilitate the detection and positioning of the growth plate, instead ofsensors.

FIGS. 6A and 6B are perspective views collectively illustrating abiological scanner 60 that includes another useful feature. Inparticular, biological scanner 60 includes a first set of footings 62disposed on a first side of scanner 60 and a second set of footings 64disposed on a second side of scanner 60. In this example, the first setof footings 62 are disposed on a bottom side and the second set offootings 64 are disposed on a top side of scanner 60. However, othersides of the scanner could alternatively or additionally have footings.

In accordance with this aspect of the invention, the insertion slot 65that receives a biological growth plate is disposed on a right side ofscanner 60 when scanner 60 is positioned on the first set of footings 62and a front side 68 of scanner 60 is facing a user (as shown in FIG.6A). The insertion slot 65 is disposed on a left side of scanner 60 whenscanner 60 is positioned on the second set of footings 64 and the frontside 68 of scanner 60 is facing the user (as shown in FIG. 6B). In thismanner, footings disposed on various sides of scanner 60 can facilitateselective positioning of scanner 60 in inverted orientations forsimplified use by right-handed or left-handed users In other words,scanner 60 can be placed “right side-up” or “upside-down,” depending onthe desired orientation of slot 65. In this manner, footings can bedisposed on various sides of scanner 60 to facilitate flexibility interms of the input and output locations of the scanner. A user mayposition scanner 60 on a given set of footings 62 or 64 based on theuser's preferences or the work environment in which scanner 60 is used.Footings on a back side of scanner may also be desirable for someapplications. In this case, if scanner was positioned on footingsdisposed on its back side, front side 68 would be facing upward and slot65 would be oriented on an uppermost side of scanner 60.

FIG. 7 is a flow diagram illustrating operation of an exemplarybiological scanner in accordance with an embodiment of the invention.FIG. 7 will be explained with reference to biological scanner 30 ofFIGS. 3-5.

Biological scanner 30 receives a biological growth plate (71). Forexample, a user may insert the biological growth plate into biologicalscanner 30 between guide mechanism 35 and actuator 47. Upon detection byfirst sensor 52A, one or more of rollers 36, 37 draw the growth plate toa first location (72), e.g., corresponding to second sensor 52B.Actuator 47 presses the growth plate against platen 41 (73), andbiological scanner 30 generates a first image of the biological growthplate (74). For example, illuminators 33A, 33B and possibly backilluminators 42 that may for part of actuator 47 can illuminate thegrowth plate and imaging device 32 can generate one or more images.

Actuator 47 then releases the growth plate from platen 41 (75). Rollers36, 37 draw the growth plate to a second location (76), e.g.,corresponding to third sensor 52C. Actuator 47 presses the growth plateagainst platen 41 (77), and biological scanner 30 generates a secondimage of the biological growth plate (78). By way of example, the firstimage may correspond to an image of indicia on the growth plate and thesecond image may correspond to an image of a growth area on the growthplate.

Actuator 47 then releases the growth plate from platen 41 (79), androllers 36, 37 eject the growth plate from scanner 30 (80). The imagesare then processed (81). In particular, the images are processed tocount bacterial colonies on the growth plate. In one example, the imagesare internally processed within biological scanner 30 via an internalprocessor (not shown). In that case, biological scanner 30 would displayor otherwise output bacterial counts. In another example, the generatedimages can be sent to an external computer for processing. In that case,the external computer would display or otherwise output bacterialcounts.

A number of embodiments of a biological scanner have been described. Forexample, sensor arrangements have been described which facilitatesensing and positioning of the growth plate in a plurality of locationsfor imaging. Automated transport mechanisms and positioning actuatorsare also described for automating the intake and positioning of a growthplate inside a biological scanner. Additional embodiments are directedto features such as a hinged door that facilitates access to thescanner, and footings disposed on various sides of the scanner tofacilitate flip-over of the scanner for simplified use by right-handedor left-handed users.

Nevertheless, various modifications may be made without departing fromthe spirit and scope of the invention. For example, one or more featuresdescribed herein may be used with or without other described features.Also, in some embodiments, the imaging device may be used to detectpositioning of the growth plate. In that case, one or more of sensorsmay be eliminated. These and other embodiments are within the scope ofthe following claims.

1. A biological scanner for scanning a biological growth medium, thescanner comprising: a transport mechanism to draw the biological growthmedium into the biological scanner; a platen within the biologicalscanner; one or more sensors to detect when the biological growth mediumis drawn to a scanning position adjacent the platen; an actuator topress the biological growth medium against the platen when the one ormore sensors detect that the biological growth medium is drawn to thescanning position; and an imaging device to generate an image of thebiological growth medium when the biological growth medium is pressedagainst the platen.
 2. The biological scanner of claim 1, wherein theactuator comprises a second platen, and a solenoid that moves the secondplaten.
 3. The biological scanner of claim 1, further comprising aprocessor that counts biological agents in the medium based on theimage.
 4. The biological scanner of claim 1, further comprising anillumination device to illuminate the biological growth medium when thebiological growth medium is pressed against the platen.
 5. Thebiological scanner of claim 4, further comprising: a first illuminationdevice to illuminate a top side of the biological medium when thebiological growth medium is pressed against the platen; and a secondillumination device to illuminate a bottom side of the biological mediumwhen the biological growth medium is pressed against the platen.
 6. Thebiological scanner of claim 1, wherein the imaging device comprises acamera.
 7. The biological scanner of claim 1, further comprising: afirst slot formed in a first side of the scanner for receiving thebiological growth medium; and a second slot formed in a second side ofthe scanner for ejecting the biological growth medium followinggeneration of the image.
 8. The biological scanner of claim 1, whereinthe transport mechanism comprises a set of rollers.
 9. The biologicalscanner of claim 8, further comprising a hinged door, wherein a firstsubset of the rollers are disposed on the hinged door and a secondsubset of the rollers abut the first subset of the rollers when thehinged door is closed.
 10. The biological scanner of claim 8, wherein afirst subset of the rollers are spring biased against a second subset ofthe rollers.
 11. The biological scanner of claim 8, further comprising amotor to drive at least a subset of the rollers to draw the biologicalgrowth medium into the biological scanner.
 12. The biological scanner ofclaim 1, further comprising: a first sensor to detect insertion of thebiological growth medium and cause the transport mechanism to draw thebiological growth medium into the scanner; and a second sensor to detectwhen the biological growth medium is drawn to the scanning position andcause the actuator to press the biological growth medium against theplaten.
 13. The biological scanner of claim 1, further comprising: afirst sensor to detect insertion of the biological growth medium andcause the transport mechanism to draw the biological growth medium intothe scanner; a second sensor to detect when the biological growth mediumis drawn to a first scanning position and cause the actuator to pressthe biological growth medium against the platen; and a third sensor todetect when the biological growth medium is drawn to a second scanningposition and cause the actuator to press the biological growth mediumagainst the platen.
 14. The biological scanner of claim 13, wherein thefirst scanning position corresponds to an indicia location on thebiological growth medium and the second scanning position corresponds toa location of biological agents on the biological growth medium.
 15. Thebiological scanner of claim 1, further comprising: a first set offootings on a first side of the biological scanner; and a second set offootings on a second side of the biological scanner such that thebiological scanner can be positioned on either of the first or secondset of footings.
 16. A biological scanner for scanning a biologicalgrowth medium, the scanner comprising: a housing; an imaging device togenerate an image of the biological growth medium when the biologicalgrowth medium is within the housing; a first set of footings on a firstside of the housing; and a second set of footings on a second side ofthe housing such that the biological scanner can be positioned on eitherof the first or second set of footings.
 17. The biological scanner ofclaim 16, further comprising: a first slot formed in a first side of thehousing for receiving the biological growth medium; and a second slotformed in a second side of the housing for ejecting the biologicalgrowth medium following generation of the image, wherein the first slotis disposed on a right side of the scanner when the scanner ispositioned on the first set of footings and a front side of the scanneris facing a user and the first slot is disposed on a left side of thescanner when the scanner is positioned on the second set of footings andthe front side of the scanner is facing the user.
 18. A biologicalscanner for scanning a biological growth medium, the scanner comprising:a housing formed with a hinged door; an imaging device to generate animage of the biological growth medium when the biological growth mediumis within the housing; a set of rollers to draw the biological growthmedium into the biological scanner, the set of rollers including a firstsubset of rollers disposed on the hinged door; and a second subset ofrollers that abut the first subset of the rollers when the hinged dooris closed.
 19. The biological scanner of claim 18, wherein a firstsubset of the rollers are spring biased against a second subset of therollers when the hinged door is closed.
 20. The biological scanner ofclaim 18, wherein a second subset of the rollers are spring biasedagainst a first subset of the rollers when the hinged door is closed.21. The biological scanner of claim 18, further comprising a motor todrive at least some of the rollers to draw the biological growth mediuminto the biological scanner.
 22. A biological scanning systemcomprising: a biological scanner for scanning a biological growthmedium, the scanner comprising a transport mechanism to draw thebiological growth medium into the biological scanner, a platen withinthe biological scanner, one or more sensors to detect when thebiological growth medium is drawn to a scanning position adjacent theplaten, an actuator to press the biological growth medium against theplaten when the one or more sensors detect that the biological growthmedium is drawn to the scanning position, and an imaging device togenerate an image of the biological growth medium when the biologicalgrowth medium is pressed against the platen; and a computer coupled tothe biological scanner and including a processor that counts biologicalagents in the medium based on the image.
 23. The system of claim 22,wherein the actuator comprises a second platen, and a solenoid thatmoves the second platen.
 24. The system of claim 22, wherein the imagingdevice comprises a camera.
 25. The system of claim 22, wherein thetransport mechanism comprises a set of rollers, the biological scannerfurther comprising a hinged door, wherein a first subset of the rollersare disposed on the hinged door and a second subset of the rollers abutthe first subset of the rollers when the hinged door is closed.
 26. Thesystem of claim 25, wherein a first subset of the rollers are springbiased against a second subset of the rollers.
 27. The system of claim22, the biological scanner further comprising: a first sensor to detectinsertion of the biological growth medium and cause the transportmechanism to draw the biological growth medium into the scanner; and asecond sensor to detect when the biological growth medium is drawn tothe scanning position and cause the actuator to press the biologicalgrowth medium against the platen.
 28. The system of claim 22, thebiological scanner further comprising: a first sensor to detectinsertion of the biological growth medium and cause the actuator to drawthe biological growth medium into the scanner; a second sensor to detectwhen the biological growth medium is drawn to a first scanning positionand cause the actuator to press the biological growth medium against theplaten, wherein the imaging device generates a first image associatedwith the first scanning position; and a third sensor to detect when thebiological growth medium is drawn to a second scanning position andcause the actuator to press the biological growth medium against theplaten, wherein the imaging device generates a first image associatedwith the first scanning position, wherein the processor identifies anindicia associated with the biological growth plate based on the firstimage and counts biological agents in the medium based on the secondimage.
 29. The system of claim 28, wherein the first scanning positioncorresponds to an indicia location on the biological growth medium andthe second scanning position corresponds to a location of biologicalagents on the biological growth medium.
 30. The system of claim 22, thebiological scanner further comprising: a first set of footings on afirst side of the biological scanner; and a second set of footings on asecond side of the biological scanner such that the biological scannercan be positioned on either of the first or second set of footings. 31.A method comprising receiving a biological growth medium in a biologicalscanner; drawing the biological growth medium to a first scanningposition within the scanner; generating a first image of the biologicalgrowth medium; drawing the biological growth medium to a second scanningposition within the scanner; and generating a second image of thebiological growth medium.
 32. The method of claim 31, wherein the firstimage includes indicia and the second image includes biological agentson the biological growth medium.
 33. The method of claim 31, furthercomprising ejecting the biological growth medium from the biologicalscanner
 34. The method of claim 31, further comprising processing thefirst image to identify the biological growth medium.
 35. The method ofclaim 31, further comprising processing the second image to countbiological agents in the medium based on the second image.
 36. Themethod of claim 31, further comprising: pressing the biological growthmedium against a platen when the medium is at the first scanningposition; releasing the biological growth medium from the platen aftergenerating the first image; pressing the biological growth mediumagainst a platen when the medium is at the second scanning position; andreleasing the biological growth medium from the platen after generatingthe second image.
 37. The method of claim 31, further comprisingprocessing the first image to identify the biological growth medium andprocessing the second image to count biological agents in the mediumbased on the second image, wherein processing the first image andprocessing the second image occur internal to the biological scanner.38. The method of claim 31, further comprising: communicating the firstand second images to a computer; processing the first image to identifythe biological growth medium; and processing the second image to countbiological agents in the medium based on the second image, whereinprocessing the first image and processing the second image occur in thecomputer, the computer being external to the biological scanner.
 39. Abiological scanner for scanning a biological growth medium, the scannercomprising: a transport mechanism to draw the biological growth mediuminto the biological scanner; a platen within the biological scanner; animaging device to detect when the biological growth medium is drawn to ascanning position adjacent the platen and to generate an image of thebiological growth medium when the biological growth medium is pressedagainst the platen; and an actuator to press the biological growthmedium against the platen when the imaging device detects that thebiological growth medium is drawn to the scanning position.